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DY: Dynamik und Statistische Physik

DY 28: Glasses I (joint session DF/DY)

DY 28.9: Vortrag

Dienstag, 9. März 2004, 12:00–12:15, H23

Mapping supercooled liquids on simple trap models for the long-time dynamics: justification and consequences — •Andreas Heuer, Aimorn Saksaengwijit, and Katharina Hobbeling — Institut für Physikalische Chemie, Corrensstr. 30, D-48149 Münster

For a long time it has been realized that the potential energy landscape (PEL) viewpoint is useful for characterizing supercooled liquids and glasses. To this end, one considers the high-dimensional vector of all particle coordinates as a point moving on the surface of the total potential energy. It turns out from computer simulations of a binary mixture Lennard-Jones system that the dynamics can be described as a random-walk between stable structures on the PEL, denoted metabasins [1]. Furthermore it turns out that the metabasins act as traps. Escaping a metabasin requires an activation energy which is proportional to the depth in the PEL. Thus the dynamics of the glass-forming liquid is very similar to the dynamics within a trap model. Some consequences of this mapping for the application of modern equilibration routines like parallel tempering are discussed.

[1] B. Doliwa and A. Heuer, Phys. Rev. Lett. (in press).